In general, an RFID (Radio Frequency Identification) concerns to one of the automatic recognition fields using radio waves. The RFID is also called a radio frequency recognition system configured to recognize pre-stored predetermined information wirelessly using radio waves such as ultra short waves or long waves.
Principle of the RFID system is to recognize information recorded in a tag via a wireless communication. The recorded information belongs to RFID fields for example a bar code label, a magnetic stripe, etc. An RFID reader receives information stored in the tag via an antenna. The RFID reader recognizes and analyzes the received information, and obtains inherent and circumstance information for a product where the tag is applied or, incorporated.
The RFID system uses signals to be free from ambient environment such as snow, rain, dust and magnetic flux, for example. Furthermore, the recognition speed is fast such that recognition is possible even in transit, and at a predetermined long distance. The RFID system is provided with an intrinsic ID (identification) in the manufacturing process to substantially prevent itself from being fabricated or counterfeited.
The RFID system includes for example a reader, an antenna, a tag, etc. The antenna performs an intermediation function between the tag and the reader. A power and a signal are sent to the tag via the antenna via a wireless communication, so that the tag is activated. Further, a response from the tag is received via the antenna. Meanwhile, the RFID system uses a NFC (Near Field Communication) scheme and a mobile RFID (mRFID) scheme. In other words, the NFC is a short-range high frequency wireless communication technology which enables the exchange of data between devices over about a short distance. The RFID system of the NFC scheme, for example, uses a frequency (e.g., 13.56 MHz) of a high frequency band with low power to transmit data at a distance between 10 cm and 60 cm. Since the NFC scheme provides high security, the NFC scheme has been used in applications for example a traffic card, mobile payment, etc. The NFC scheme is standardized in ISO/IEC 18092.
The NFC scheme can perform a short distance radio communication using various frequency signals including 125, 135 and 900 kHz in addition to the 13.56 MHz.
An NFC device has such advantages of communicating or being compatible with existing information devices including portable wireless terminals and notebook computers through exchanges of address books, game and MP3 files. The NFC technology using a predetermined frequency band is high in its safety and already in use for public transportation and mobile phone payment. The NFC technology may be utilized as a future information terminal capable of obtaining various information by approaching a tag stored with predetermined information.
A mobile phone embedded with NFC chips is in an early distribution stage and the NFC technology is expected to be widely adopted in mobile terminals including portable wireless terminals.
The portable terminals embedded with NFC chips are generally mounted with an antenna through which to communicate with an external reader. However, the NFC antenna mounted on the portable wireless terminal cannot communicate with the reader unless mutually close such that increase of recognition distance with the NFC antenna is required.